What is the management and treatment for a patient with placenta previa?

Management and Treatment of Placenta Previa

Placenta previa requires careful management with hospitalization for symptomatic patients, activity modification, avoidance of digital vaginal examinations, and planned cesarean delivery at 35-36 weeks to reduce maternal and fetal morbidity and mortality. 1, 2

Diagnosis and Classification

• Placenta previa is diagnosed when the placenta overlies the internal cervical os, occurring in approximately 0.4% of pregnancies in the third trimester 1
• Transvaginal ultrasound is the diagnostic modality of choice for accurate assessment of placenta previa 1, 3
• Digital pelvic examination should be avoided until placenta previa has been excluded to prevent triggering hemorrhage 1
• Placenta previa is common in early pregnancy (42.3% at 11-14 weeks, 3.9% at 20-24 weeks) but most resolve by 28 weeks 1

Risk Assessment

• Risk factors include prior cesarean delivery, pregnancy termination, intrauterine surgery, smoking, multifetal gestation, increasing parity, and advanced maternal age 3, 2
• Women with placenta previa and prior cesarean deliveries should be evaluated for placenta accreta spectrum disorder, which significantly increases morbidity 1, 3
• Women with one episode of bleeding may be at increased risk for subsequent bleeding episodes 1

Management Approach

Antepartum Management

• Women with asymptomatic placenta previa before 28 weeks can continue moderate-to-vigorous physical activity (MVPA) 1
• After 28 weeks, women with placenta previa should avoid moderate-to-vigorous physical activity but can maintain activities of daily living and low-intensity activity such as walking 1
• Hospitalization is recommended for women with:
  • Active bleeding 1
  • Preterm labor 1
  • Preterm premature rupture of membranes 1
  • Limited access to emergency care or significant distance from hospital 1
• For women without these complications, decisions about hospitalization should be individualized based on risk factors and patient preference 1
• Optimize hemoglobin values during pregnancy; treat anemia with oral or intravenous iron as needed 1

Delivery Planning

• Delivery should take place at an institution with adequate blood banking facilities and multidisciplinary expertise 1, 3
• Planned cesarean delivery is recommended for complete placenta previa at 35-36 weeks after administration of antenatal corticosteroids 3, 4
• Preoperative coordination with anesthesiology, maternal-fetal medicine, neonatology, and expert pelvic surgeons is essential 1
• Notify blood bank in advance due to frequent need for large-volume blood transfusion 1

Intraoperative Management

• The most accepted approach is cesarean delivery with careful surgical planning 1
• Considerations for cesarean delivery include:
  • Dorsal lithotomy positioning to allow access to vagina and optimal surgical visualization 1
  • Vertical or wide transverse skin incisions may be used based on operator judgment 1
  • Inspect the uterus after peritoneal entry to determine placental location and optimize uterine incision approach 1
  • When possible, make the uterine incision away from the placenta 1
  • After delivery of the fetus, leave the placenta in situ if there is evidence of abnormal placental attachment 1
  • Attempts at forced placental removal can result in profuse hemorrhage and should be avoided 1

Special Considerations

• For cases with suspected bladder involvement, consider ureteric stent placement and collaboration with urologic surgeons 1
• Prophylactic intraoperative uterine artery embolization may reduce blood loss in cases of major placenta previa, though evidence is limited 4
• Regional anesthesia for cesarean delivery in women with placenta previa is generally safe 3

Complications and Management

• Major complications include massive hemorrhage requiring blood transfusion 3, 4
• In cases of placenta accreta spectrum, cesarean hysterectomy may be necessary 1
• Close monitoring of volume status, urine output, blood loss, and hemodynamics is critical during surgery 1

Follow-up Care

• Monitor for postpartum hemorrhage in the immediate postpartum period 3
• Ensure adequate iron supplementation and follow-up of hemoglobin levels if significant blood loss occurred 1

By following this structured approach to the management of placenta previa, maternal and perinatal morbidity and mortality can be significantly reduced.